JPS60131407A - Position detector for light pen - Google Patents

Abstract

PURPOSE:To perform position detection accurately in a short time by reading the contents of a brightness memory within a specific region from the center point of a visual field, and deciding on the coordinate position of a target point from an address position corresponding to signals with logic ''1'' among the read signals. CONSTITUTION:A computer 5 executes a graph generating program to decide on position information on a graphic form, and then writes brightness information in the brightness memory 11. A scanning mechanism 12 reads the brightness information out of the brightness memory 11 synchronously with the scanning of a graphic display device 1 and displays it on the graphic display device 1. The intersection of tracking lines 7 and 8 is put in the visual field 9 of a light pen 2, and then aposition detecting mechanism 13 inputs the outer circumference of the visual field 9 and the information on the intersection of the lines 7 and 8 to the computer 5 to calculate the position coordinates (x0, y0) of the center point 11 of the visual field.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a graphic display (graphi display).
The present invention relates to a light pen position detection device for detecting the position of a figure displayed on a display device using a light pen.

[Prior art]

Figure 1 is a block diagram showing a conventional device of this type, in which (1) is a graphic display device, (2) is a graphic display device;
1 is a light pen, (31 is a display control device, (4 is
1 is a light pen control device, and (5) is a computer output.

FIG. 2 is a diagram explaining the position tracking operation by the light pen 121. In the figure, (6) is the display tube surface, (7) is the vertical tracking line, 181 is the horizontal tracking line, and 191 is the light pen 121. , is the field of view of the pen. However, in order to make the drawing easier to see, the challenge field (9) is significantly enlarged. Since the tracking lines 17+ and +8+ have higher brightness than the other parts of the display tube surface (6), when these lines 17+ and +81 are within the field of view (9), the signal is sent to the light pen (21). The calculator (5) includes a generation mechanism for the line 171, +8+, for example, the line 71 shown in Figure 2 (71 is
, change y from ymin (corresponding to the top end of the tube surface 16) to ymax (corresponding to the bottom edge of the tube surface (6)), input this to the display control device (3), and set X=x.
Perform vertical scanning according to the y value at the horizontal position of 3 to find the line (
7), and the line (8) represents x at y=y3.
n (corresponding to the leftmost edge of the tube surface 161) to xmax (corresponding to the rightmost edge of the tube surface 16)), input this to the display control device (3), and input it to the vertical position of y'')'3. horizontal scanning is performed according to the value of ljl +81.

When the light pen (2) is placed on the tube surface so that the intersection of lines 171 and 181 is within the field of view (9) of the light pen, the light pen (2) will draw a point ( 10a).

(iob,) is detected, and when line (7) is displayed, points (10c) and (10d) are detected. Each time these points are detected, an interrupt is sent from the light pen 121 to the computer (5) via the light pen control device (41).
The coordinate position of these points (toa (xl, y3)) + (1
0b(X2.)r3) ) +(10c(x3.yl)
) + (10d(X3t Determine 72 months.

In many cases, to improve the detection accuracy of these points, line (7) is combined with the scan in ymin − + ymax direction and ymax
scanning in the x −+ ymin direction, and the line 181 is
min − + scanning in xmax direction and xmax 4 x
Scanning in the min direction is performed.

When the coordinate positions of (10a) to (10d) are determined, the calculator (5) calculates X. = A CXi x2)e 7o=
A (yl”)'2) is executed, and the field of view (9) is
Determine the center position (X6p '16) of (X0yy
Tracking lines 171 and 181 are generated so that the intersection is at the position of 0).

Therefore, the field of view of the light pen (2) (9
) so that the intersection of the tracking lines t71, ;8+ is placed on the light pen (2), and when you move the position of this light pen, the positions of the tracking lines 171, 181 will move accordingly, and the intersection of S78171, 181 will be moved. is controlled so that it coincides with the center of the field of view (9), and this intersection position (Xo.

y ) is known in the calculator (5), move the position of the light pen (2) on the tube surface (6) to move the trunking H171, +8+, and move the intersection to 19'r of the desired target figure. The position of the target point has been determined by superimposing it on the desired target point.

The conventional light pen position detection device operates as described above, so it can accurately place the tracking line at the desired target point.
, 181 intersections are difficult to match. Graphic display device (1
) on the tube surface 16), the target point is hidden by the light pen (21), making it more difficult for the operator's eyes to detect this coincidence.Therefore, in conventional devices, accurate position information of the target point is obtained. In order to generate a figure to be displayed on a graphic display device, a program that performs calculations to generate the figure must be checked by software along with the data used for the calculation. By executing this program, the position of each dot on the figure is determined and displayed from the graphic display device (1) K via the display control device 1+31. In order to obtain accurate position information, among the position coordinates of the points calculated by executing calculations using the above program, use the 1i coordinate of the point closest to the position coordinate of the center position of the light pen (2) as the position coordinate of the target point. It has to be determined that the calculation by the program is time-consuming and increases the load on the computer (5).

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and in this invention, by using the position information of the brightness memory where the dot pattern of the figure is stored,
The positional coordinates of a point or line segment on the screen are accurately determined without performing any graphic generation calculations.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a block diagram showing one embodiment of the present invention.
The same reference numerals as in the figure indicate the same or equivalent parts, ``ull'' is the brightness memo I3, (l side is the scanning @ mechanism, (13) is the position detection mechanism, ``brightness memo +7'', and ``till'' is the brightness for each position on the display tube surface. This memory is read out by a scanning mechanism θ and displayed on a graphic display device (
1) is displayed as a figure on the tube surface (6). When the figure is displayed in black and white, one dot (the minimum unit of the image) on the screen 161 is stored in the luminance memory (formerly) by a 1-bit signal, and the portion where the line segment is drawn is the logical "l". '' (corresponding to high brightness), and the undrawn part of the line is stored as a logic ``0'' (corresponding to brightness 0) signal. Figures with intermediate brightness or multicolored figures It is necessary to use multiple bits to display the brightness of one dot, but for the convenience of explanation below, when displaying figures, one dot is one
Assume that the display is black and white corresponding to bits.

When the computer 51 executes a graphic generation program to determine the positional information of the graphic, the brightness information is stored in the brightness memory at the address position according to the positional information. The scanning mechanism (6) is a graphic disk display device f
In synchronization with the scanning of i+, the luminance information is read from the luminance memory Qtl and displayed on the graphic display device (11).The scanning mechanism 02 also displays tracking lines 171, which are orthogonal to each other, based on the intersection position data given from the calculation +9151. The generation of +81 is as explained in Fig. 1. When the intersection of lines +71 and 181 is captured within the field of view (9) of the light pen (2), the position detection mechanism (13) detects the outer periphery of the field of view (9). Line 171, +8
1 intersection information ((10a), (10b), (1
The positions (position information) of 0c) and (10d) are input to the computer (51), and the computer t51 calculates the position coordinates (X(1+'1o
) is calculated, and this center point u11 is given to the scanning mechanism α as new intersection position data.

Therefore, if the light pen (2) is moved while keeping the intersection of the lines (71, +81 in the field of view), the tracking lines 171 and +81 will also move along with the movement of the light pen 12, and will change the field of view (9) of the light pen (2; When the intersection of the tracking lines 171 and 181 is almost overlapped with the target point on the figure, the field of view (9) of the light beam at that time is shown.
The coordinate position (Xot y6) of the center point till is determined by the computer (5). Light pen (21)
The operation of superimposing □ on the target point of the figure to obtain the coordinate position (X0t)'0) of the center point of the field of view (9) at that time is the same as the conventional one, but the □ coordinate position (Xo.

When y(1) is determined, the calculator (5; is X. ±ΔK +
'/6±△y range position information is recorded in the brightness memo IJ (111
The brightness information within that range is read out. Since the bit whose brightness information is logical ``1'' corresponds to a line or point of the figure, the address where the bit of logical ``1'' is read within the range of xo±ΔX + )'O±Δy. The position allows accurate position information of the target line or target point to be determined.

In this case, if the values of ΔX and Δy are too small, the target point or target line will be X. ±ΔX t '16±Δy may fall outside the range, and if these values are too large, a logic [1] signal may be read out at a portion other than the target point or target line. ΔX and Δy may be determined so that the range is the same area as the field of view (9). Determining whether the logic of the signal read from the luminance memory 11.11 is "1" or "0" can be performed by a simple ratio soft circuit.

〔Effect of the invention〕

As described above, according to the present invention, by applying the light pen to a target point on a figure displayed on a graphic display device, the contents of the luminance memory within a certain range from the center point of the field of view of the light pen are read out. , the accurate coordinate position 1t' of the target point is determined from the address position corresponding to the logic rlJ signal among the read signals, so the device is inexpensive and it is easy to determine the exact coordinate position of the target point. This has the advantage of being able to make a decision in a short time and reducing the computer load.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a conventional device, Fig. 2 is a diagram explaining the position tracking operation using a light pen, and Fig. 3 is a block diagram showing a conventional device.
The figure is a block diagram showing one embodiment of the present invention. (11... Graphic display device, (21...
...Light pen, +a+...Display control device,
(5)...Calculator, Uυ...Brightness memo 9, O'
4...Scanning mechanism, [3...Position detector #lI. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa Figure 1 Figure 2

Claims (1)

[Claims] Luminance information corresponding to each dot of a dot pattern of a figure to be displayed on a graphic display device is placed at a coordinate position of the dot on the display surface of the graphic display device. a scanning mechanism for reading out the contents of the luminance memory □ and displaying it on the graphic display device in synchronization with scanning of the graphic display device; Based on the intersection position information provided by the computer to the above-mentioned scanning mechanism, vertical track jig lines and water lines with intersecting points at positions determined by the information are created.
means for displaying a flat running line on the graphic display device; - by applying the light pen to the display surface of the graphic display device such that the intersection is within the field of view of the light pen; □ and a horizontal tracking line portion, and determine the positional coordinates of the center of the field of view of the light pen based on the position of the detected portion; and the determined positional coordinates of the center of the field of view of the light pen. means for controlling the position of the center of the field of view to coincide with the position of the intersection by giving it to the scanning mechanism as the intersection position information, and the position of the center of the writing field of view and the position of the intersection coincide. 2), apply the light pen to a target point on a figure that can be displayed on the graphics display device, and select an address range corresponding to a predetermined age range from the position coordinates of the center of the visual field. Indulge the contents of the above brightness memory in
7. A position detection device for a light pen, comprising means for determining the coordinate position of the target point according to an address position from which a signal of brightness corresponding to the brightness of a point on a figure is read.